Valashar was founded in 361 DR[note 1] by Lord Ashar Tornamn, a prince and the fourth nephew of King Karaj Tiiraklar II of Tethyr.[1][2] As only fourth in line to the throne of Tethyr, Ashar sought another means to power.[1] Over fifteen years, he slowly built up an army and continuously spread the territory under his control, all in the name of the Shoon Empire.[1][2]

The largest territorial expansion came during Ashar's March, when King Ashar marched in a fifteen-month campaign,[2] without orders from either the Emperor or the king of Tethyr,[5] north as far as the High Moor by the end of summer,[5]376 DR.[2][note 1]

Unknown to most, it was the secret machinations of Emperor Shoon VI and his advisors that orchestrated these events. They hoped to eventually conquer Cormyr.[2] The Twisted Rune also tried to manipulate matters in this short-lived country.[7]

It was because of the constant expansion of Valashar and the demands for taxes along the Sword Coast[5][2] that Crown Prince Azoun I of Cormyr had the magic sword Ilbratha forged.[1][5] Wielding the blade, Cormyr's heir apparent waged a valiant campaign against Valashar and the Shoon Empire. In 376 DR, Cormyr wiped out the army of Valashar in a great battle on the Fields of the Dead before marching into Tethyr and sacking the city of Ithmong.[1][5][2]

King Ashar was executed that same year by the Shoon Empire for antagonizing King Azoun.[5]

Most of the territory of Valashar was absorbed into the kingdom of Cortryn, another short-lived kingdom, in 491 DR.[4]